The present invention relates generally to ultrasonic transducers and, more particularly, to an ultrasonic probe using ribbon cable to attach the electrical wiring to the transducer elements.
Ultrasonic transducers have been available for quite some time and are particularly useful for non-invasive medical diagnostic imaging. Ultrasonic transducers are typically formed either of piezoelectric elements or of micro-machined ultrasonic transducer (MUT) elements. The piezoelectric elements typically are made of a piezoelectric ceramic such as lead-zirconate-titanate (PZT), with a plurality of elements being arranged to form a transducer. A MUT is formed using known semiconductor manufacturing techniques resulting in a capacitive ultrasonic transducer cell that comprises, in essence, a flexible membrane supported around its edges over a silicon substrate. By applying contact material, in the form of electrodes, to the membrane or to a portion of the membrane, and to the base of the cavity in the silicon substrate, and then applying appropriate voltage signals to the electrodes, the MUT may be energized such that an appropriate ultrasonic wave is produced. Similarly, when electrically biased, the membrane of the MUT may be used to receive ultrasonic signals by capturing reflected ultrasonic energy and transforming that energy into movement of the electrically biased membrane, which then generates a receive signal.
The ultrasonic transducer elements may be arranged in a one or multi-dimensional array and combined with control circuitry forming a transducer assembly, which is then further assembled into a housing possibly including additional control electronics, in the form of electronic circuit boards, the combination of which forms an ultrasonic probe. A large number of ultrasonic elements typically comprise an array, thereby requiring a large number of electrical connections as each element should be connected to a separate electrical lead and to a ground plane.
There are different ultrasonic probes available depending on the type and the location of the tissue, organ, or other structure in the body being imaged. One of the more specialized ultrasonic probes is the transesophageal probe (TEE probe), which is formed on a long slender body. This configuration places severe limitations on the mechanical and electrical design of the probe and presents significant wiring challenges. Specifically, the TEE probe has considerable space restraints that must be observed when designing the probe. This affects both the size of the array and the volume of space available to connect each element in the array to a suitable wiring system. While known one-dimensional arrays typically have a fine horizontal pitch (pitch is the center to center distance between the elements in the array) and a coarse vertical pitch, many proposed two-dimensional arrays are finely pitched in both dimensions having horizontal and vertical pitch dimensions on the order of 100-160 xcexcm (microns).
The TEE probe is an invasive probe, and, as such, space inside the probe body for making electrical connections is severely limited. In the past, it has been difficult to design a TEE probe having a significant number of electrical leads within the space allowed by the probe design, and it has been difficult to connect a large number of transducer array elements to their respective individual conductors.
Therefore, it would be desirable to be able to be able to connect a large number of transducer elements to their respective conductors in the limited space available in an ultrasonic transducer probe.
An ultrasonic transducer probe uses one or more ribbon cables to attach the transducer elements to the probe wiring. Electrical conductors within a first ribbon cable attach to corresponding lands on an end of an integrated circuit and, electrical conductors within additional ribbon cables attach to corresponding lands on circuit boards. The circuit boards distribute the electrical signals from the attached ribbon cables to additional lands on another end of the integrated circuit.
Other systems, methods, features, and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims.